Can you provide a citation for Harry Gold? All I find is a chemist convicted of spying for the Soviets.
I find [1] which outright declares the etymology is from the economic term, and that it was popularized in medicine by Peter Rudd in 1979, or from a 1962 punning usage referring to literal gold salts.
The economic sense of a gold specie currency has uses going back to at least 1764 [3][4][5].
Both publications notably do not capitalize 'gold standard'.
The first book simply calls it 'aptly named', pointing out the aptronym, but does not attribute the name to Harry Gold.
The NCBI says that Fisher (the famous statistician) established placebo with randomized control trial 'gold standard'.
It is coincidental that Harry Gold, a pharmacologist, is the progenitor of placebo therapy in American medicine - as the NCBI notes, placebo therapy is "as old as medicine itself".
The second one has "Gold", and "gold standard" but it does not link the two. The first links the two, but there are a number of sources here and at the least they disagree.
And the Johari window is named after two guys named Joe and Harry.